Can I fetch transactions for a specified period, say January 1 to December 31?

You can definitely fecth or record transactions for a specific date, nieju. I'd be glad to help you do that.

There are actually two options on how you can do it in in QuickBooks Self-Employed. I'd also be glad to share these options with you. 

First, you can manually add transactions and enter the date that you want. Here's how:

1. Go to the Transactions menu and select Add transaction.
2. Select the date that you want in the Date field.
3. Enter all other details of the transaction such as the amount, description, and category.
4. Click Save.

Second, you can download a CSV copy of your banking transactions for a specific date. Then, import it in QuickBooks Self-Employed. Here's an article about this option for more details: Add Older Transactions to QuickBooks Self-Employed.

Let me also add a couple more articles for additional references: 

• Categorize Transactions in QuickBooks Self-Employed
• Updates to Expense Categories in QuickBooks Self-Employed

Please don't hesitate to tag me and ask more questions if you need anything else. We'd be more than happy to jump in and help you right away.